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                                                                   Exhibit 31.1

                                 CERTIFICATION

I, Eleanor L. Thomas, certify that:

   1.  I have reviewed this quarterly report on Form 10-Q of World Monitor
       Trust--Series B ('Series B');

   2.  Based on my knowledge, this quarterly report does not contain any untrue
       statement of a material fact or omit to state a material fact necessary
       to make the statements made, in light of the circumstances under which
       such statements were made, not misleading with respect to the period
       covered by this quarterly report;

   3.  Based on my knowledge, the financial statements, and other financial
       information included in this quarterly report, fairly present in all
       material respects the financial condition, results of operations and cash
       flows of Series B as of, and for, the periods presented in this quarterly
       report;

   4.  Series B's other certifying officers and I are responsible for
       establishing and maintaining disclosure controls and procedures (as
       defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for Series B and
       we have:

        a)  designed such disclosure controls and procedures, or caused
            such disclosure controls and procedures to be designed under
            our supervision, to ensure that material information relating
            to Series B, including its consolidated subsidiaries, is made
            known to us by others within those entities, particularly
            during the period in which this quarterly report is being
            prepared;

        b)  evaluated the effectiveness of Series B's disclosure controls
            and procedures and presented in this report our conclusions
            about the effectiveness of the disclosure controls and
            procedures, as of the end of the period covered by this
            report based on such evaluation; and

        c)  disclosed in this report any change in Series B's internal
            control over financial reporting that occurred during Series
            B's most recent fiscal quarter that has materially affected,
            or is reasonably likely to materially affect, Series B's
            internal control over financial reporting; and

   5.  Series B's other certifying officers and I have disclosed, based on our
       most recent evaluation of internal control over financial reporting, to
       Series B's auditors and the board of directors of the managing owner of
       Series B:

        a)  all significant deficiencies and material weaknesses in the
            design or operation of internal control over financial
            reporting which are reasonably likely to adversely affect
            Series B's ability to record, process, summarize and report
            financial information; and

        b)  any fraud, whether or not material, that involves management
            or other employees who have a significant role in Series B's
            internal control over financial reporting.

Date:  August 11, 2003                   /s/ Eleanor L. Thomas
                                         --------------------------------------
                                         Eleanor L. Thomas
                                         President (chief executive officer)
                                           of the managing owner of Series B